00015 - Breast cancer and prostate cancer cases occuring within the PLCO cohort will be evaluated in a nested case-control manner to assess risks associated with early reproductive characteristics, including likely early hormonal profiles (via genetic inference) 00022 - The National Cancer Institute is studying the health effects among persons receiving large numbers of immunizations while employed as civilians at Fort Detrick, Maryland. These individuals were employed in a variety of positions which required them to enter areas where they were potentially exposed to a variety of infectious agents. To protect individuals against these exposures, immunizations were administered to them by the medical staff at the Fort whenever their job required entry to particular areas. Some individuals received as many as 50 or more immunizations to a particular agent, and some persons were immunized to as many as 30 different infectious agents. While these immunizations protected the individuals against specific pathogens, the long term effects of such challenges to the immune system are unknown. A study of 100 persons receiving multiple immunizations at this facility found no immediate clinical illness as a result of their immunizations. However, the study did show several laboratory aberrations following intensive immunizations that suggest the possibility of long term deleterious effects. We are conducting a follow-up study of this hyper-immunized cohort to examine their mortality experience relative to their immunization history. The results of this study may add to our understanding of the effects of high levels of immune stimulation and disease development, including cancer. 00400 - a multi-center case-control study of bladder cancer 1978. There are 10 SEER centers.